Weft detecting system for looms



Dec. 9, i947. o. v. PAYNE 2,432,171

wEFT DETECTING SYSTEM FOR LoOMs l 3 Sheets-Sheet 1 Filed June 30, 1945 OSCAR PAY Nye:

@u ma@ ATTORNEY Dec 9, 1947. v. PAYNE WEFT DETECTING SYSTEM FOR LOOMS Filed June 50, 1945 3 Sheets-Sheet 2 OSCAR V. PAYNE ec. 9, H941 Q v, PAYNE 2,432,171

WEFT DETECTING SYSTEM FOR LOOMS Filed June 3o, 1945 3 sheets-sheet s INVENTOR OSCAR V. PAYNE fm.. 7W@

ATTORNEY Patented Dec. 9, 1947 UNI ED STATES PATENT OFFICE WEFT DET-ECTING SYSTEM LOOMS Application June 30, 1945, Serial No. 602,439

Claims.

This invention relates to a weft detecting 'system -for a loom wherein a beam of light 'is utilized to actuate a Vphotoelectric cell for the purpose of initiating a change in loom operation, such as replenishment of weit, and it is the general object `of the invention to use in such a system a transparent bobbin which when uncovered at weft exhaustion will retract the beam of light and cause the latter to produce an 'eifective change in the illumination of the photoele'ctrlc cell.

It has been proposed heretofore to utilize ph'otoelectric detecting means in looms for determining the amount of weft remaining on a bobbin, but 's'o far as I am aware these systems have required Vthat the bobbins be provided with ferrules having reflecting surfaces or holes 'to permit light passage. The ferrules are likely to become dented from repeated use, and holes through the bobbins not only weaken the latter but crimp the parts of the weft which bridge the holes. In the weaving of wefts of such fineness as to require a delicate detecting system this crimping is objectionable. It is an important object of my present invention to provide a ph'ot'oelectri'c weft detecting system wherein the actuating beam of light is transmitted through a transparent b-obbin barrel having a continuous and uninterrupted circumference on which weft can be wound.

In the usual automatic loom there isa sin'gl'e vshuttle boX at the replenishing end which is occupied b-y the active shuttle on alternate picks of the loom, b-ut on the intervening picks the shuttle box is empty. When the lay reaches front center on the intervening picks the light unit will operate the cell unit unless some provision is made to prevent actuation of the cell. It is another object of my present invention to provide means wherein some part of the electrical system controlled by the photoelectric cell is opened on the aforesaid intervening picks of the loom. As shown hereinafter this result is accomplished preferably by means of the actuating lever oi a well-known type of loom.

In carrying my invention into ei'ect I have found that it is possible to use any one of several optical systems for directing a light beam from the light unit source toward the photoelectric cell unit. In the simplest of these systems a small beam of light is directed toward the bobbin barrel which is so located as to prevent the beam ofV light from falling Aon the photoelectric cell when an ample supply of weft is on the bobbin. When the supply becomes exhausted the beam of light travels through the transparent part of the bobbin and thence to the photoelectric cell unit. In a diieren't optical system I have utilized a lens for the purpose of converging light upon the bobbin in such a l2 Way that the beam of light falling on the bobbin is smal-ler 4than .the latter so that the bobbin will ordinarily cast a shadow on the photoelectric cell and prevent its operation. By use of the lens it is .possible to move the source o'f light ata greater distance from the photoelectric cell, a condition which is advantageous in certain types ol l'ooin. In still another optical system, I may employ two lenses 'which will permit an even greater distance between the source of light and the photoelectric cell. In all of these systems the transparent hobbin barrel causes the emerging beam of light to be directed toward the photoe'lectric cell.

With these and 'other objects lin view which will appear Vas the description proceeds, my invention resides in the fcomhma'tion and arrangement `of parts hereinafter described and set forth.

In the accompanying drawings, wherein 'a convement embodiment of my invention is set forth,

1 is a side 'elevation of a loom, partly in section, showing the preferred 'form of my improved -detecting system with the parts in position to give an indication of weft exhaustion,

Fig. 2 is a plan View on an enlarged scale looking in -t-h'e Adirection of arrow 2, Fig, 1,

Fig. 3 is an enlarged longitudinal section through a part Iof the b'obbin used in my invention,

Fig'. "4 is a vert-ical section on Vline --ZL Fig. 3,

Fig. 5 is a diagrammatic view showing the optical system with two lenses `and the electric circuits used in the preferred form of my invention,

Fig. 6 is a diagrammatic 'view showing the rst modiiication of the optical system utilizing one lens,

Fig. 7 is a diagrammatic View showing the second modification of the optical system in which no lens iis* used, and l Fig. 8 vshows 'the path 'of light emerging 'from a 'solid bobbin.

Referring lpart-cularly to Fig. 1, I have shown a well known type Yof loom to which my invention can be applied, but I do not wish `to be limited to this type 'of loom in the practice `of my invention. The loom frame `II) vsupports a lay Il driven from a top or crank 'shaft I2 which rotates once for each pick of the l'oom. The lay is mounted on lay swords one of which is shown at I3, and these 'swords move pivot'ally about a common center, such as the rocker pin IB. The l'ay is provided with Aa shuttle Ybox I5 including a front wall I6 and a rear binder 17 pvoted to the lay as at I8, see Fig. 2. The lay has a 4slot 2i) which receives a picker stick 21 having a picker 22 'secured to the upper end thereof.

A magazine M supplies two different types of weft or reserve bobbins and rocks about a sta- 26 is connected to the shifting boxes and in cludes an actuating lever 21 which is rocked regularly in a two-pick cycle by a cam 28 secured to the bottom shaft 29 which rotates once in every two picks of the loom. Lever 21 rocks about 'a stationary stud 30 on which is also pivoted aV normally stationary setting lever 3|. Lever 3| is provided with a lifting shelf 32 for cooperation with a dog 33 pivoted on lever 21, but the dog is normally in such position that it clears the shelf 32 when the forward end of lever 21 rises.

The cam 28 is so designed that dog 33 starts to rise when the shuttle is at the non-automatic or drop box side of the loom and after the completion of the shuttle box shifting period. The dog reaches its highest position during the ensuing forward movement of the lay and remains up until the time of picking from the mag.- azine end, or until the lay has reached appro-ximately its mid position on the backward stroke thereof. The forward end of lever 21 is therefore up while the shuttle is at the magazine end of the loom and is down when the lay is at front center with the shuttle in the shifting boxes at the opposite end of the loom. This timing of the lever 21 is usual in the type of loom shown in Fig. 1, but I employ it as will be set forth hereinafter to prevent indication of exhaustion by the detector system when the shuttle is at the drop box side of the loom.

The dog 33 is under control of a mechanism designated generally at C and including a solenoid 35 operatively connected to the mechanism C in such a way that when the solenoid is energized one or the other of two indicating ngers 36 and 31 is moved from normal to indicating position in the path of the dog 33 so that as the latter rises it is directed toward the ledge 32. The mechanism for controlling the longitudinal posi tion of the controller C includes a flexible cable 40 connected to the drop boxes at the opposite end of the loom and attached to the lower end of a lever 4| pivoted as at 42. Pivots 30 and 42 are mounted on a stationary support 43 which may also carry a sheave or pulley 44 around which the cable 40 is trained.

The upper end of lever 4I is attached as at 45 to a forwardly extending rod 46 attached to the control mechanism C. When the drop boxes are down the control mechanism C is in one position so that finger 36 will be lifted upon energization of solenoid 35, but when the drop boxes rise an accompanying longitudinal movement of controller C will cause the other nger 31 to move to indicating position upon operation of the solenoid. Only one of the fingers 3B and 31 can guide the dog 33 at a time.

The mechanism thus far described in connection with Fig. 1 of itself may be as set forth in prior Patents Nos. 2,054,174, 2,054,192, and 2,128,- 974, and operates in the usual manner, that is, actuation of solenoid 35 when an exhaustedshuttle is in the shuttle box I will trip one or the other of the ngers 35 or 31, and after the shut tle has been picked to the opposite end of the loom and time allowed for shifting of the shuttle boxes the forward end of lever 21 will rise so that dog 33 will be caused to engage lifting ledge 32 if the empty shuttle is to return to the magazine end. 1

The present invention contemplates the use of a photo-electric cell which is actuated by light transmitted through a transparent bobbin. Shuttle W in box l5 carries a bobbin B which in its general form may be similar to those customarily used and will have a butt 50 provided with A the usual rings 5l which are gripped by the spring jaws 52 of the shuttle, see Fig. 2. The bobbin has a barrel 53 part at least of which is transparent. As shown in Fig. 3 the transparent part near the bobbin butt is designated at 54 and may be made as set forth in my copending application Serial No. 602,435, filed on even date herewith. The bobbin barrel has an uninterrupted or circumferentially continuous surface K circular in transverse section on which weft is wound. r[he shuttle is formed with front and back walls 55 and 56, respectively, in which are located horizontally aligned front and back slots 51 and 58, respectively. These slots align with slots 59 and 60 formed in the iront and back shuttle box walls I6 and l1, respectively. When the shuttle is properly boxed part 54 of the babbin will be in line with the slots just described and the shuttle box will therefore have a horizontal light transmitting passage extending therethrough whenever the bobbin barrel is depleted of weft.

The bobbin barrel may be solid, or it may be provided with a bore GI for the reception of the spindle of a winding machine. Because of the fact that the barrel of the bobbin is circular in cross-section and` is formed of a light transmitting material it possesses properties which are advantageous when used with an optical system for the excitation of a photoelectric cell.

Mounted on the back of the lay behind slot 50 and in position for actuation by a beam of light passing through the bobbin and the aforesaid slots is a photoelectric cell designated generally at 65. The form of cell 65 shown is illustrative of but one of several such cells which are usable with my invention. I have found in practice that it may be the type of cell used in photographic phctometers. The cell 65 as set forth herein is permanently connected to the lay so that its relationship to the bobbin in the shuttle box is fixed whenever the shuttle is properly boxed.

Any one of several optical systems may be used for supplying the light beam for passage through the bobbin and actuation of the cell 65, and I show herein three different optical systems. The preferred form shown in Figs. 1, 2 and 5 is used in looms where it is difficult to locate the light source near the shuttle box because of interfering loom parts. A box-like structure 61 mounted on a stand 68 secured to the loom frame l0 has located therein a source of light S which may be a small incandescent lamp. Behind the lamp are located front and back lenses L and L2, respectively. The rear wall of casing 61 has an aperture 69 therein for the passage of light. The effect of the lenses is to converge the light from the source upon the bobbin barrel.

Fig. 5 shows diagrammatically the relationship of the parts within the casing 61 with respect to the bobbin and the photoelectric cell 55, and also shows the controlling circuits. Ordinarily the photoelectric cell is not energized so that any circuits which it might control are dead. When the shuttle is in box I5 and the lay moves forwardly light will pass from the source S through the two lenses L and L2 and will be converged so that the beam of light falling on the bobbin will be of somewhat smaller diameter than the diameter of the bobbin barrel. So long as -suflicient weft is wound on the bobbin the light will be stopped by the weft and the photoelectric cell will remain unenergized. When the weft is exhausted, however, light will pass through the bobbin and be directed by it toward cell 65 and cause an effective change in the illumination of the cell, causing it to set up a small electric potential, Current will then now through the following detecting circuit: cell B5, wire 1I), coils |I and 'I2 of a galvanometer indicator G, wire 13, closed switch I4, and wire 'I5 back tothe other side of cell t5. The wiring for the cell shown in Fig. 5 is diagrammatic and no attempt has been made to trace any circuit internal to the cell, since this circuit is well known and cells of the type suitable for the present invention are ordinarily provided with binding posts or the like to which the wires 'I0 and 'I5 can be connected. The slight current that is derived from the photoelectric cell is suflicient to energize the coils II and l2, the effect of which is to cause movement of a small armature 'I6 to which is attached an arm TI. The latter will be moved to the right as indicated in dotted lines in Fig. 5, whereupon current ilows in the following relay circuit: transformer T, wire 18, relay coil 19, wire SQ, Contact 8|, arm TI, wire 82, and wire 83 back to the transformer. Energization of this circuit causes the relay coil to attract its armature Sli, whereupon current flows in the following solenoid circuit: transformer T, wire 18, wire 85, solenoid 35, wire S6, armature B4, contact 81, wire 88 and wire 33 back to the transformer.

The resulting energization of solenoid 35 effects the setting of one or the other of the indicating ngers 36 or 3l as already described and upon subsequent return of the depleted shuttle it will be replenished with a fresh bobbin drawn from the magazine M in usual manner.

The switch 'III included in the rst or detecting circuit is controlled by lever 2l and is mounted on a small support 95 secured to the stationary stand 43. This switch has an arm S6 which is mechanically engaged by the underside of the lever 21 to close switch 'Ill when the lever 21 is down, a condition existing when shuttle W is in shuttle box I5. When the shuttle is at the opposite side of the loom and the lay is at front center the cell 65 Will be in forward position where the beam of light passing through the empty shuttle box I5 falls on it, but energizatio-n of the cell under these conditions occurs when lever 2l is up, hence the detecting circuit is open at switch la and the coils 'II and 'I2 remain unenergized. It is because of the control exercised by lever 27 over switch 'III that the detector will not indicate weft exhaustion and effect energization or solenoid 35 when the lay reaches front center position and the shuttle is at that end of the loom opposite the detecting system.

Instead of the optical system shown in Fig. 5 wherein two lenses are employed, I may use the modification shown in Fig. 6, wherein only one lens is employed. In this rst modification the casing IIIII may be similar to the casing 61 and have located therein the source of light S and also a lens L3. The rear wall of the casing |00 is provided with an aperture IIlI through which the beam of light passes after leaving the lens L3. In this modiiication the light is converged by the lens on the transparent part of the bobbin, and the light emerging from the bobbin will be directed toward the cell 65. This modification operates in much the same manner as does 'the preferred form of the invention, the cell 65 being energized whenever the bobbin is depleted of weft and the shuttle is on the detecting side of the loom. The circuits shown in Fig. 5 will be used in connection with this modification.

In the second modification shown in Fig. 7 and usable when the optical system can be located close to the lay I dispense with the lenses and permit the light to pass directly from its source to the transparent bobbin. In this modification the source S is located in a casing |05 similar to the casings already described except that the aperture |06 at the rear thereof is regulated as to size by shields or light stops I 07 and |08. These shields are mounted on casing I5 and are held in adjusted position by set screws |09 by means of which the size or width of the aperture |06 may be adjusted so that that part of the light beam falling on the transparent bobbin will be smaller than the diameter of the bobbin.

In all forms of the invention it is desirable that the beam of light which falls on the bobbin barrel shall have a cross section less than the diameter of the barrel so that the latter when covered with even a thin layer of weit will cast a shadow on the cell 65. I have found that the diierent forms of optical systems described cause different degrees of excitation of the photoelectric cell 65, but in each instance enough light falls on the cell to actuate it suliciently to cause arm 'I1 to engage contact 8 I.

In the normal operation of the loom on detecting beats the shuttle box I5 will be empty when the lay is on back center and will remain empty during the rst part of the forward movement of the lay until the shuttle enters the box when the lay is approximately at bottom center and half way between its front and back extreme positions. Because of the fact that the intensity of light varies inversely as the square of the distance between the cell 65 and the optical system, the intensity of the light can be so regulated that cell 65 will not be energized when the lay is in its rearward position and can be energized only when the lay is near its front center position, and after the shuttle has entered box I5. After front center the lay moves rearwardly, but the shuttle is not picked out of the box I5 until the lay has reached top center, or approximately the mid point in its rearward sweep. After picking cell 65 will be too far behind the optical system to be energized even though the shuttle box be empty. In this way actuation of cell 65 cannot occur during that part of the movement of the lay when switch 'I4 is closed and shuttle W is absent from box I5.

For Varying the intensity of the light source some such arrangement as shown in Fig. 5 may be used, where the power lines II2 and H3 are connected to the lamp S by wires IIlI and II5, sliding contact IIB, variable resistance II'I and wire I I8. In this way the intensity of light emit-A ted by the lamp can be adjusted so that it will not energize the cell E5 when box I5 is empty and lay IIY is behind shuttle boxing and picking po- SitOIlS.

The transparent barrel of the bobbin acts more or less in thel capacity of a lens in the effect which it has on the light emerging from it. When the bobbin is tubular as already set forth herein the light appears to spread after leaving the bobbin, this spreading being indicated by lines p-p", pZ--p2, and 273-123.111 Figs. 5, 7 and 6, respectively. By reason of this spreading the beam of light falls on the entire exposed surface of the photoelectric cell 65. When the bobbin barrel is solid as indicated at I 20 in Fig. 8 the beam of light appears to come to a focus a short distance behind the bobbin, but beyond the point of focus the rays spread. The rays in this instance are indicated by lines 214-494. With the solid transparent bobbin the beam of light falling on the cell appears to be slightlyA more intense than is the case with the tubular bobbin.

From the foregoing it will be seen that I have provided a photoelectric weft detecting system for looms wherein a transparent bobbin normally covered by weft casts a shadow upon the photoelectric cell to prevent its actuation, but at weft exhaustion the barrel becomes uncovered and permits passage of the light beam through the bobbin and toward the cell. Beca-use of the fact that the curved surfaces of the transparent bobbin barrel act somewhat in the capacity of lenses' the light rays emerging from it are directed toward the cell 65. Furthermore, the switch 14, being under control of lever 21, prevents actuation of the solenoid 35 when the lay is on front center and the shuttle is at the end of the loom opposite the detecting system. It will also be seen that different forms of optical systems may be used for directing the light from the source S on to the bobbin barrel. Furthermore, the bobbin is provided with a transparent barrel having a continuous uninterrupted surface on which weft can be wound and for this reason the bobbin can be placed in the shuttle at transfer in the same manner as in ordinary looms and there will be no crimping of the weft as in the case of previous detecting systems of this type.

Having thus described my invention it will be seen that changes and modifications may be made therein by those skilled in the art without departing from the spirit and scope of the invention and I do not wish to be limited to the details herein disclosed, but what I claim is:

l. In a loom having a photoelectric weft detector operative upon an eiTective change of illumination thereof to initiate a change in loom operation, a source of light, and a bobbin having a barrel part of which is transparent and formed with a circumferentially continuoussurface circular in transverse section and located between the source of light and said photoelectric weft detector at the time of weft detection and made of material having an index of refraction greater than that of the surrounding air, said part of the barrel when uncovered by weft exhaustion refracting the light from said source and directing the refracted light onto said photoelectric weft detector to cause an effective change in the illumination thereof.

2. In a loom having a photoelectric weft detector operative upon an effective change of illumination thereof to initiate a change in loom operation, a source of light, and a bobbin having a barrel part of which is located between the source of light and said photoelectric weft detector at the time of weft detection, said part of the barrel being made of transparent material and formed with a circumferentially continuous weft carrying surface substantially circular in transverse section and having an index of refraction greater than that of the surrounding air, and said part of the barrel when uncovered by weft exhaustion refracting and transmitting light from said source and directing the transmitted refracted light onto said photoelectric weft detector to cause an effective change in the illumination thereof.

3. In a loom having a photoelectric weft detector operative upon an effective change of illumination thereof to initiate a change in loom operation, a sourceof light, and a bobbin formed with a transparent weft holding part having a greater light refracting power than the air between the source and the detector and having a circumferentially continuous surface which is lo-f cated between said source and said detector at the time of weft detection, said weft holding part being eifective when uncovered due to weft ex-l haustion to refract light from said source and cause the refracted light to produce an effective change in the illumination of said detector by said source of light.

4. In a loom having a photoelectric weft detector operative upon an effective change of illumination thereof to initiate a change in loom operation, a source of light and a light transmitting system between said source of light and said photoelectric weft detector at the time of weft detection, said system including a bobbin barrel having a weft carrying part circular in transverse section and formed with solid transparent material having a higher index of refraction than the surrounding air and having a continuous uninterrupted curved surface effective when said surface is uncovered due to weft exhaustion to bend the rays of light from said source of light and cause the bent rays to produce an effective change in the illumination of said photoelectric weft detector.

5. In a loom having a photoelectric weft detector operative upon an effective change of illumination thereof to initiate a change in loom operation, a source of light, and a light transmitting system between said source of light and said weft detector at the time of weft detection, said system including a bobbin having a weft carrying part formed of transparent material having a higher index of refraction than the surrounding air and formedwith a continuous uninterrupted weft carrying surface circular in transversesection, and a lens focusing light from said source onto said part of the barrel when said part is uncovered due to weft exhaustion to cause the rays of light from said source of light to be bent by refraction in a direction to produce an eifective change in the illumination of the photoelectric weft detector.

OSCAR V. PAYNE.

REFERENCES CITED l The following references are of record in the lle of this patent:

UNITED STATES PATENTS Numb er 

